1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
// Copyright 2011 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// Coding tools configuration
//
// Author: Skal (pascal.massimino@gmail.com)
#include "../webp/encode.h"
//------------------------------------------------------------------------------
// WebPConfig
//------------------------------------------------------------------------------
int WebPConfigInitInternal(WebPConfig* config,
WebPPreset preset, float quality, int version) {
if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_ENCODER_ABI_VERSION)) {
return 0; // caller/system version mismatch!
}
if (config == NULL) return 0;
config->quality = quality;
config->target_size = 0;
config->target_PSNR = 0.;
config->method = 4;
config->sns_strength = 50;
config->filter_strength = 60; // mid-filtering
config->filter_sharpness = 0;
config->filter_type = 1; // default: strong (so U/V is filtered too)
config->partitions = 0;
config->segments = 4;
config->pass = 1;
config->show_compressed = 0;
config->preprocessing = 0;
config->autofilter = 0;
config->partition_limit = 0;
config->alpha_compression = 1;
config->alpha_filtering = 1;
config->alpha_quality = 100;
config->lossless = 0;
config->exact = 0;
config->image_hint = WEBP_HINT_DEFAULT;
config->emulate_jpeg_size = 0;
config->thread_level = 0;
config->low_memory = 0;
config->near_lossless = 100;
#ifdef WEBP_EXPERIMENTAL_FEATURES
config->delta_palettization = 0;
#endif // WEBP_EXPERIMENTAL_FEATURES
// TODO(skal): tune.
switch (preset) {
case WEBP_PRESET_PICTURE:
config->sns_strength = 80;
config->filter_sharpness = 4;
config->filter_strength = 35;
config->preprocessing &= ~2; // no dithering
break;
case WEBP_PRESET_PHOTO:
config->sns_strength = 80;
config->filter_sharpness = 3;
config->filter_strength = 30;
config->preprocessing |= 2;
break;
case WEBP_PRESET_DRAWING:
config->sns_strength = 25;
config->filter_sharpness = 6;
config->filter_strength = 10;
break;
case WEBP_PRESET_ICON:
config->sns_strength = 0;
config->filter_strength = 0; // disable filtering to retain sharpness
config->preprocessing &= ~2; // no dithering
break;
case WEBP_PRESET_TEXT:
config->sns_strength = 0;
config->filter_strength = 0; // disable filtering to retain sharpness
config->preprocessing &= ~2; // no dithering
config->segments = 2;
break;
case WEBP_PRESET_DEFAULT:
default:
break;
}
return WebPValidateConfig(config);
}
int WebPValidateConfig(const WebPConfig* config) {
if (config == NULL) return 0;
if (config->quality < 0 || config->quality > 100)
return 0;
if (config->target_size < 0)
return 0;
if (config->target_PSNR < 0)
return 0;
if (config->method < 0 || config->method > 6)
return 0;
if (config->segments < 1 || config->segments > 4)
return 0;
if (config->sns_strength < 0 || config->sns_strength > 100)
return 0;
if (config->filter_strength < 0 || config->filter_strength > 100)
return 0;
if (config->filter_sharpness < 0 || config->filter_sharpness > 7)
return 0;
if (config->filter_type < 0 || config->filter_type > 1)
return 0;
if (config->autofilter < 0 || config->autofilter > 1)
return 0;
if (config->pass < 1 || config->pass > 10)
return 0;
if (config->show_compressed < 0 || config->show_compressed > 1)
return 0;
if (config->preprocessing < 0 || config->preprocessing > 7)
return 0;
if (config->partitions < 0 || config->partitions > 3)
return 0;
if (config->partition_limit < 0 || config->partition_limit > 100)
return 0;
if (config->alpha_compression < 0)
return 0;
if (config->alpha_filtering < 0)
return 0;
if (config->alpha_quality < 0 || config->alpha_quality > 100)
return 0;
if (config->lossless < 0 || config->lossless > 1)
return 0;
if (config->near_lossless < 0 || config->near_lossless > 100)
return 0;
if (config->image_hint >= WEBP_HINT_LAST)
return 0;
if (config->emulate_jpeg_size < 0 || config->emulate_jpeg_size > 1)
return 0;
if (config->thread_level < 0 || config->thread_level > 1)
return 0;
if (config->low_memory < 0 || config->low_memory > 1)
return 0;
if (config->exact < 0 || config->exact > 1)
return 0;
#ifdef WEBP_EXPERIMENTAL_FEATURES
if (config->delta_palettization < 0 || config->delta_palettization > 1)
return 0;
#endif // WEBP_EXPERIMENTAL_FEATURES
return 1;
}
//------------------------------------------------------------------------------
#define MAX_LEVEL 9
// Mapping between -z level and -m / -q parameter settings.
static const struct {
uint8_t method_;
uint8_t quality_;
} kLosslessPresets[MAX_LEVEL + 1] = {
{ 0, 0 }, { 1, 20 }, { 2, 25 }, { 3, 30 }, { 3, 50 },
{ 4, 50 }, { 4, 75 }, { 4, 90 }, { 5, 90 }, { 6, 100 }
};
int WebPConfigLosslessPreset(WebPConfig* config, int level) {
if (config == NULL || level < 0 || level > MAX_LEVEL) return 0;
config->lossless = 1;
config->method = kLosslessPresets[level].method_;
config->quality = kLosslessPresets[level].quality_;
return 1;
}
//------------------------------------------------------------------------------
|